Hi there
My Ford KA failed its MOT yesterday. On the failure sheet it said ?insufficient reserve rear brake pedal movement? and the guy at the garage said that there was too much travel in the pedal. I presume this means it goes to far towards the floor with the engine running.
I have done the following:
- Blead through all 4 brakes (used half a bottle of fluid). Front ones seemed a little gassy on first couple of pumps but fine after.
- Checked disks (seem fine) and pads (at least 4mm tread left)
- Cleaned rear brakes (inside of drums)s
- Observed cylinders to be neither seized of leaking
- Observed shoes to have 2/3 remaining tread
- Re-set rear self adjuster to zero and heard them clicking when applying brakes after refitting drums
Advisory notices were ? ?hand brake borderline pass? and ?rear brake efficiency borderline pass?.
The guy at the garage said it was probably a case of adjusting the rear shoes. I have read on a couple of other forums that the rear self adjusters can be inaccurate ? surely if I could hear them clicking then they are working, or not?! Does it sound like the cylinders are shot?
Also I heave read that the front pads can be troublesome on the KA. Would this cause travel in the pedal? I would have thought not as they are also self adjusting. Does the application of the pedal not just move the callipers a certain distance? If the pads/ disks became powdery / flexible when worn then I could justify changing them.
Any advice would be much appreciated as I have spent about 5 hours working on them this weekend and the pedal seems to be as it was in the first place. I know I?m a newbie but I have just successfully changed two suspension coils on the KA today so in return for the advice I will post a ?How too? guide shortly including the pics?
Thanks in advance!
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Fit new self adjusters.
They'll make the clicking noise, but, when worn, they slip back, giving long pedal travel. They aren't expensive.
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Slacken off the handbrake first and try to adjust the shoes so they just start to catch the drum.
But if they do not adjust enough or far too much there worn out a common problem it's a ratchet with little teeth and they wear.
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Thanks for the responses.
I managed to sort this out after a phone call to a rather helpful Clutch and Brake specialist who I found in Yellow Pages. It went in for its re-test yesterday and passed the MOT.
Apparently, the self adjusters within the brake drums on Fords require manually adjusting as the self adjusting function does not remove enough slack. I had to remove the drum several times, each time I pressed the pedal so the adjuster did one click. Upon re-fitting the drums and tapping it with a hammer I had to get it so that it was a snug fit over the brake shoes. The idea is so that you can just hear a very slight binding but not to the extent that you need to apply a force to turn the drum (otherwise they will overheat).
As a result the pedal needs depressing less to gain the necessary brake efficiency as the pistons are having to move less every tie the brakes are applied.
Whilst doing this I must have re-fitted the 27mm central wheel hub nut about half a douzen times. Is this acceptable - The Haynes says change it after 3 re-fits but they may just be covering their backs.
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Whilst doing this I must have re-fitted the 27mm central wheel hub nut about half a douzen times. Is this acceptable
No. you undo the 4x bolts at the back to remove the ford drums now you may have damaged the bearing.
Ford reccomend the bolts the front hub nut is only for replacing the bearing.
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OK thanks, ill bear that in mind in future. The reason I did not undoo the 4 bolts at the back was because in the past I have found it tricky to put the brake drum back on especially when the shoes are adjusted to they are snug.
Ill anticipate possible wheel bearing replacement in the future but if it is dangerous in the mean while then please let me know?
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Ill anticipate possible wheel bearing replacement in the future but if it is dangerous in the mean while then please let me know?
Well it won't be me that knows you will if it gets very noisey!
There is a lip on the outer edge of the drum from were the shoes have worn this needs to be removed by either a buffing coarse wheel or skim/grind off this will be much easier to re fit.
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Ill put some new nuts on to be on the safe side and keep my ears open incase the bearing starts singing. I did make sure the bits that came out were clean, greaced and well aligned when I put them back in.
Thanks for you advice bigtee.
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personally if the nuts stayed in the cage i wouldnt replace them
as said grind the lip off the drum and adjust up manually, slide the drum on and pump pedal up, you will hear another click and job done check drum not sticking with handbrake off then put the nut on
simples
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Yep I did remove the lip and the pedal is feeling allot better - hence passed MOT.
The nuts did stay in the cages but I found when removing them that a couple of the spikes at the rear of the cage had snapped off.
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Its now a week since its passed its MOT and Im noticing that the rear drum on the N/S is getting much hotter than the one on the other side. I have opened the drums up again and slacked the self adjusters by a couple of clicks so there is no binding what so ever when cold. After a half hour journey when you touch it you have to let go after a couple of seconds as its so hot.
I am aware that undoing the Hub nut to originally remove the drums was an error. I do remember the outer bearing cone falling out at the time so I cleaned and re-graced it before putting it back in.
Is this likely to be damage to the bearing that is creating the heat? There is NO noise or play what so ever. If yoou spin the wheel just after a journey there is resistance and you can hear the shoes binding and upon removing the drum you have to wiggle it off as the shoes are so snug. The heat appaears to be the same at the centre of the drum as it is on the circumference.
Im not sure whether its the shoes causinng the heat and expansion or the bearing.
Any ideas?
Thanks
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It could be that the bearing is what is initially getting warm and it is causing the brake parts to expand and this is why you can hear the shoes binding after a journey. Or maybe the self adjusters are not working right and it is over adjusting the brake up. My gut instinct from the problems and remedies that you have had of late is that the bearing will be the most likely suspect.
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Replace that bearing like i said thats only for removing the bearing not to adjust the shoes.
Make sure wheel cylinder not seized and handbrake cable is free.
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Thanks for the advaice.
Luckily I went to the MOtor Fators before they closed today and got a bearing kit.
Just one thing: The Haynes says "to remove the bearing cups from the hub, drive them out with a suitabhle punch". Is this easy or will I need to take it to a garage as you have to do on a Ford Focus?
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Sorry what I meant was, can this be done without the use of a press?
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Yes i use a drift to knock out the shell's and use a large socket to put them back in, grease it very well.
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I changed the wheel bearing this afternoon. Put in a brand new one with plenty of greace with a new Hub nut. Cost £27.
There is no difference atall! Getting a bit fed up with it now.
The drum is aprox 60% as hot as the front disk but hard to say really. I might just put a new wheel cylinder in tomorrow for the sake of it.
I have noticed though that when applying the brake pedal there is a breif clicky creaking sound comming from the wheel. Its not the noise that the adjusters make. Could it be that the cylinder is ceasinng up and hence moving the shoes in sudden bursts?
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Fit new adjusters.
If the adjusters work properly, there's no need to adjust them with the drum off.
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The teeth on the adjusters do not apear worn.
I was told by a couple of garages that they need manually adjusting.
When you slacken off the adjuster and put the drum back on, you can hear it self adjusting when depressing the pedal.
If you adjust them so that they are just starting to bind against the drum, then re-open the drum the next day, they will not have slipped back.
I presume they are designed to remove slack as the shoes wear as opposed too creating it when they expand? They therefore seem to be functioning as they should be.
When cold they are fine, wheels spin round with no binding. After a half hour drive, the wheel will spin say 1 revolution, but everythinng is snug and hot. Its as if the wheel cylinder is not fully retracting the pistons causing constant friction and expansion. (or something to the same effect?)
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Rear drums almost always need manual adjustment prior to the drums going back on.
Jack up the back of your car so that both wheels are clear of the ground.
Do the wheels spin without binding?
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Rear drums almost always need manual adjustment prior to the drums going back on.
I agree, thats the only way I got it through the MOT.
Do the wheels spin without binding? >>
Yes they do (at the start of a journey) but at the end of say a half hour journey the O/S has binding and will only spin one rev and the N/S spins like it did before the journey.
I have tried slackening off the adjuster to zero and letting it self adjust with the drum on. Then after a half hour journey I have the same problem. Upon taking it apart I discover that the adjuster on the hot side is 2 notches slacker than the one on the other side. This is measured from reference scores that I marked on the adjusters when setting them up manually from MOT.
If the adjusters were responsible for creating slack in the system when the shoes expand then I would say they are faulty. However they are supposed to do the complete opposite and remove slack as the shoes wear which they are doing (to the usual Ford extent).
Im going to change the wheel cylinder this morning.
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Are you sure that this 'hot' brake isn't just working more efficiently than the other side and the the other side may be lacking in performance? How hot does it get? Are you sure you are not chasing a problem that doesn't actually exist?
How about taking it to an MOT station for a roller brake test. That will show up if it is binding to any great degree or not if you take when it is 'hot'.
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The springs should pull the shoes back (along with retracting the slave cylinder piston) as far as the adjuster will allow anyway. I would remove just the adjuster and use an assistant to press the brake pedal gently and then release it so you can see whether the springs are pulling the shoes back to the centre position.
I really can't see it being a slave cylinder fault, I suppose there is an outside chance that it could be a collapsed flexi hose to that brake. What about the handbrake mechanism, is that all free and working?
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It is possible that the other brake is lacking in performance, your correct. I would say that it gets 60% as hot as the front disk after a half hour drive. There was an advisory at the MOT saying that reaer brake efficiency was borderline (this was before maually adjusting it). The heat that both of the drums on my Focus creates is the same as the cooler drum on the KA.
I will get some assistance in the next hour and test the springs whilst the adjuster is disabled. I have slackened off the brake cable so the shoe is at rest.
After checking the springs and changing the cylinder (its only a tenner) Im going to call it a day and assume that the problem does not exist.
I have taken a photo - not sure how tro atach it.
BTW the milage is 45k genuine.
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I'd replace the wheel cylinder as you intend to, then I reckon all will be well.
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...........and Inded all is well! PROBLEM SOLVED!
As advised, I got someone to press the brake pedal and observe the springs. They appeared to work OK but the right hand side was slow to retract. I then removed the shoe assembly from the back plate and squeezed both pistons between fingure and thumb whilst the pedal was pressed. The clylinder on the right hand side took about 3 times as mush effort and time to squeen back in than the one on the left.
I went down to the Motor Parts store and they had 2 types of cylinder. A generic one for Escorts, Fiestas and some KAs for £7.99 but the one I needed had a circular section on the back and was £20.99. But I guess I would have paid at leaste this in labour alone if I had taken it to a garage. Upon fitting it I put a very small smear of greace on some of the pivoting parts (as per they Haynes).
Just driven over to Bristol and back and its thankfully a luke warm feeling as is the other side.
For anyone with an over heating brake drum I would seriously recommend following the above "squeeze test" procedure in the first place before you go investing in new bearings, shoes, drums etc. I guess the cylinder was on its way out and working in a semi-seized state and thats possibly why there was an advisory notice at the MOT saying the "rear brake efficiency was borderline pass".
Thanks for everyone comments.
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a lesson learned, seized brakes are hotter than seized wheel bearings , and possibly the twain shall meet eventually
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Funny Isnt it. If it hadnt had failed the MOT on pedal travel then the problem would naver have come to attention making the brakes vulnerable to seizure / overheating which in turn can cause a hose to burst giving no brakes atall!
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